Developer
Encoders, formatters, generators, and converters for everyday developer tasks — all client-side.
JSON Formatter & Validator
Beautify, minify and validate JSON in your browser — separate input/output panes, pinpoint syntax errors by line and column, sort keys, and download.
DeveloperBase Encoder — Base64, Base32, Base58 & Base64URL
Encode and decode text with Base64, Base32, Base58 or Base64URL — pick the alphabet from a dropdown. Unicode-safe, free, 100% in your browser.
DeveloperURL Encoder & Decoder
Percent-encode text for safe use in URLs, or decode an encoded URL back to readable text. Free, in your browser.
DeveloperHash Generator (MD5 & SHA)
Generate CRC32, MD5, SHA-1, SHA-256, SHA-384 and SHA-512 hashes of any text or file, instantly and privately in your browser.
DeveloperID Generator — UUID, NanoID, ULID, ObjectID & MAC
Generate UUID v4, UUID v7, NanoID, ULID, MongoDB ObjectID or MAC addresses in bulk — pick the type, set a count, copy. Includes a UUID validator. Free, in your browser.
DeveloperJSON to CSV Converter
Convert a JSON array of objects to CSV, or CSV back to JSON — quoting handled correctly. Free, in your browser.
DeveloperPassword Generator
Generate strong random passwords or memorable word passphrases in your browser. Free, nothing sent anywhere.
DeveloperJWT Decoder
Decode a JWT and verify HMAC (HS*) and RSA/ECDSA (RS/PS/ES) signatures in-browser — with your secret or a public key — plus a live expiry countdown. Token and keys never leave your device.
DeveloperUnix Timestamp Converter
Convert Unix/epoch timestamps to human dates in any time zone, with a live epoch clock and ISO 8601, RFC 2822, date & millisecond formats. Free, in-browser.
DeveloperQR Code Generator
Create a QR code for a URL, Wi-Fi network or contact — custom colors, a center logo, download as PNG or SVG. Free, in your browser.
DeveloperRegex Tester
Test a regular expression against your text, highlight matches and groups, and preview a replace. Free, in your browser.
DeveloperMarkdown to HTML
Convert Markdown to clean HTML with a live preview and one-click copy. Free, safe, in your browser.
DeveloperHTML Entity Encoder / Decoder
Encode text to HTML entities or decode entities back to text — named, decimal and hex. Free, in your browser.
DeveloperJSON to Code — TypeScript, Go, Rust, Python & more
Paste JSON and generate type definitions in TypeScript, Go, Rust, Python, Java, Kotlin, Swift or C# — pick the language from a dropdown. Free, no upload.
DeveloperCron Expression Explainer
Translate any cron expression into plain English and preview the next run times — free, no upload, in your browser.
DeveloperText Encrypt & Decrypt (AES)
Encrypt and decrypt text with a password using AES-256-GCM — entirely in your browser, nothing is ever uploaded.
DeveloperText to Binary
Convert text to binary, hexadecimal, or decimal and back — instantly and privately, using UTF-8 so any character round-trips.
DeveloperString Escape / Unescape
Escape text for source code (newlines, tabs, quotes, backslashes, \uXXXX) and unescape it back — instantly, in your browser.
DeveloperURL Parser
Break a URL into protocol, host, port, path, fragment and a table of query parameters — instantly and privately.
DeveloperHTTP Status Codes
A searchable reference of HTTP status codes — 200, 301, 404, 500 and more — with plain-language meanings. In your browser.
DeveloperBitwise Calculator (AND, OR, XOR, NOT, Shift)
Compute AND, OR, XOR, NOT and bit shifts on two 32-bit integers and see the result in decimal, hex and binary — runs 100% in your browser, no upload.
DeveloperASCII Table
Searchable ASCII table (codes 0–127) with decimal, hex, binary, and the character or control-code name — runs 100% in your browser with no upload.
DeveloperCSV to Markdown Table
Convert CSV data into a clean GitHub-flavored Markdown table with header and delimiter options — runs 100% in your browser with no upload.
DeveloperHTML to Text Converter (Strip HTML Tags)
Paste HTML and instantly get clean plain text with tags removed, entities decoded and line breaks preserved — runs 100% in your browser, nothing is uploaded.
DeveloperPassword Strength & Entropy Checker
Estimate a password's entropy in bits, get a Very weak to Very strong rating, and see which character sets it uses — runs 100% in your browser, nothing is uploaded.
DeveloperUnicode Character Inspector
Break any text into its Unicode code points and see the U+ codepoint, decimal value, UTF-8 bytes, and HTML entity for every character — runs 100% in your browser with no upload.
DeveloperHMAC Generator (SHA-256, SHA-1, SHA-512)
Generate an HMAC of any message with a secret key using SHA-256, SHA-1, or SHA-512 — output as hex, running 100% in your browser with nothing uploaded.
DeveloperIP Subnet Calculator (IPv4 CIDR)
Enter an IPv4 CIDR like 192.168.1.10/24 and instantly get the network, broadcast, host range, subnet mask, wildcard mask, host counts and address class/type — runs 100% in your browser, no upload.
DeveloperLine Numberer
Add sequential line numbers to any text with custom start, separator, and zero-padding — runs 100% in your browser with no upload.
DeveloperMIME Type Lookup
Look up the MIME type for a file extension (and vice versa) from a searchable table of ~66 common web, document, image, audio, video, archive and font types — runs 100% in your browser with no upload.
DeveloperQuery String Builder
Build a properly URL-encoded query string from key/value pairs, with an optional base URL — runs 100% in your browser, nothing is uploaded.
DeveloperUTM Builder — Campaign URL Tracking Link Generator
Build campaign tracking URLs with utm_source, utm_medium and utm_campaign tags in seconds — runs 100% in your browser, no upload, no sign-up.
DeveloperChmod Permission Calculator
Convert Unix file permissions between symbolic (rwxr-xr--) and octal (754) with a live checkbox grid — runs 100% in your browser with no upload.
DeveloperJSON Diff
Compare two JSON documents and see every added, removed, and changed key with its full path — runs 100% in your browser with no upload.
DeveloperPunycode Converter (IDN ⇆ xn--)
Convert internationalized domain names between Unicode and Punycode (the xn-- ASCII form) in both directions — runs 100% in your browser, no upload.
DeveloperHex Dump
Turn any text into an xxd-style hex dump with byte offsets, hex bytes, and an ASCII gutter — runs 100% in your browser with no upload.
DeveloperJSON to XML Converter
Convert JSON into clean, indented XML with a live preview and one-click copy — runs 100% in your browser with no upload.
DeveloperData Extractor — Pull Emails, URLs & More from Text
Extract emails, URLs, phone numbers, hashtags, @mentions or IP addresses from any block of text, deduped and ready to copy — runs 100% in your browser, no upload.
DeveloperDelimiter Converter
Convert tabular text between comma, tab, semicolon, pipe, and space delimiters with a live preview — runs 100% in your browser with no upload.
DeveloperMeta Tags Generator
Generate SEO, Open Graph, and Twitter Card meta tags from your page title, description, URL, and image — runs 100% in your browser with no upload.
Developerrobots.txt Generator — Build a Crawler Rules File Online
Generate a valid robots.txt file with User-agent, Allow, Disallow, Crawl-delay and Sitemap directives — runs 100% in your browser, no upload, no sign-up.
DeveloperSQL IN Clause Generator
Paste a list of values, one per line, and instantly build a SQL IN (...) clause with optional quoting and a column name — runs 100% in your browser with no upload.
DeveloperCSV to SQL INSERT Generator
Paste CSV and instantly build SQL INSERT statements with a table name, header, and delimiter options — runs 100% in your browser with no upload.
Developer.env to JSON Converter
Convert a .env file to JSON and back with two live, editable boxes — runs 100% in your browser with no upload.
DeveloperMarkdown Table of Contents Generator
Generate a nested Markdown table of contents with anchor links from your headings instantly — runs 100% in your browser with no upload.
DeveloperCrontab Generator
Build a cron expression from simple presets and fields, with a plain-English summary of when it runs — 100% in your browser, no upload.
Developercurl Command Builder
Build a ready-to-run curl command from a method, URL, headers and body — runs 100% in your browser, nothing is uploaded.
DeveloperJWT Generator (HS256/384/512)
Create a signed HMAC JWT from a JSON payload and secret — runs 100% in your browser, nothing is uploaded.
DeveloperJSON Flatten & Unflatten
Flatten nested JSON into dot/bracket key paths and rebuild it back, with a live two-way preview — runs 100% in your browser with no upload.
DeveloperTwo's Complement Converter (8/16/32-bit Binary & Hex)
Convert a signed integer to its two's complement binary and hex at 8, 16 or 32 bits, and decode binary back to signed decimal — runs 100% in your browser, no upload.
DeveloperGray Code Converter (Decimal ⇄ Binary ⇄ Gray Code)
Convert between decimal, binary and Gray code with instant three-way boxes — runs 100% in your browser, nothing is uploaded.
DeveloperINI to JSON Converter
Convert INI config files into clean JSON with a live preview and one-click copy — runs 100% in your browser with no upload.
DeveloperResistor Color Code Calculator
Pick the color of each band on a 4- or 5-band resistor and instantly read its resistance in ohms plus tolerance — runs 100% in your browser with no upload.
DeveloperCSS Minifier
Minify CSS to shrink file size — strips comments and whitespace and collapses rules, running 100% in your browser with no upload.
DeveloperISBN Validator (ISBN-10 & ISBN-13)
Check whether a book's ISBN-10 or ISBN-13 has a correct checksum and instantly see which standard it is — runs 100% in your browser, nothing is uploaded.
DeveloperLuhn Checker & Check Digit Calculator
Validate a card, IMEI or account number with the Luhn checksum and compute its check digit — runs 100% in your browser, no upload.
DeveloperBBCode to HTML Converter
Convert BBCode markup to clean HTML instantly — runs 100% in your browser with no upload and no sign-up.
DeveloperJSONL to JSON Array Converter
Convert JSON Lines (NDJSON) to a pretty JSON array and back, two ways, live as you type — runs 100% in your browser with no upload.
DeveloperSemver Checker & Version Comparator
Parse a semantic version into major, minor, patch, prerelease and build parts and compare two versions by precedence — runs 100% in your browser, nothing is uploaded.
DeveloperYAML ⇄ JSON Converter
Convert YAML to JSON and JSON back to YAML, both directions, with clear error messages — 100% in your browser, no upload.
DeveloperSQL Formatter & Beautifier
Format and beautify messy SQL with proper indentation and uppercase keywords, for MySQL, PostgreSQL, SQLite and more — 100% in your browser.
DeveloperHTML Formatter & Minifier
Beautify HTML with clean indentation or minify it to a single compact line — script, style and pre content preserved — 100% in your browser.
DeveloperXML Formatter
Beautify, minify or validate XML with proper indentation — paste, format, copy. 100% in your browser, no upload.
DeveloperBarcode Generator
Generate Code 128, EAN-13, UPC-A and Code 39 barcodes and download them as PNG or SVG. 100% in your browser, no upload.
DeveloperJavaScript Beautifier
Format and pretty-print minified or messy JavaScript and JSON with proper indentation. 100% in your browser, no upload.